Curtain-type closure



Dec. 25, 1956 H. N. s'rAA-rs 2,775,354

CURTAIN-TYPE CLOSURE' Filed Feb. 9. 1952 United States Patent() CURTAIN-TYPE CLOSURE Henry N. Staats, Chicago, Ill. vApplication February 9, 1952, Serial No. 270,810

6 Claims. (Cl. 214-21) The present invention is concerned with an improved type of closure for use in conjunction with various types of article treating apparatus.

`One of the primary purposes of the curtain-type closures of the present invention is to provide entrance and exit closures for an article treating apparatus in which articles to be treated are passed into and through 'a chamber where some operation is performed on the article. The closures' ofthe present invention provide means for forming temporary end closures for the treating chamber while not interfering with the normal How of articles being conveyed into the treating chamber and 1 being removed therefrom.

The closures of the present invention may be applied tonumerous types of treating apparatus, typical among which are sand blasting, washing, spray coating, degreasing apparatus, and the like. In each of these treatments,

it is desirable to prevent droplets of particles which strike the article during treatment from leaving the enclosure and being carried into adjoining areas. Another type of treating apparatus -with which the closures of the present invention can be employed is typied by a heat t .the enclosure while still permitting passage of articles through the enclosure.

Another object of the present invention is to provide an improved curtain-type closure for use with an endless belt-type of conveying system to prevent particles or droplets within a treating enclosure from *leaving the enclosure. Y

Another object of the present invention is to provide a lcurtain-type closure for furn-aces arranged totreat a continuous stream of articles.

Still another object of the invention is to provide a 'method for treating articles in a treating chamber while minimizing the transfer of thetreating chamber atmosphere outside the chamber. Other objects and features of the present invention will be apparent to those skilled in the art from the following description of the attached sheet of drawings.

In the drawings:

Figure l is a generally schematic view, with parts in elevation of a spraying chamber, a conveying system, and a curtain-type closure;

Figure 2 is av fragmentary view in elevation of a modied form of the invention illustrating one manner of attaching the curtain to the supporting structure;

Figure 3 is a cross-sectional view taken substantially along the line III-III of Figure 2;

Figure 4 is a fragmentary schematic view with parts in elevation of still Ianother modified form of the present mce invention illustrating a different means for securing the individual curtains to the curtain-supporting structure;

Figure 5 is an isometric view of the curtain-supporting structure illustrated in Figure 4, with one curtain only shown thereon for purposes of clarity;

Figure 6 is a schematic view of a still further modied form of the present invention in which the curtains are contained on an endless belt; `and Figure 7 is a fragmentary view illustrating in detail the construction of the curtains used in theform of the invention illustrated in Figure 6.

As shown on the drawings:

In Figure 1, reference numeral 10 denotes generally an enclosure for conducting a spray treatment of articles, the enclosure 10 being provided with openings 11 and 12 at opposite ends thereof through which the articles to be treated are passed into and through the spraying chamber. An endless conveyor belt 13, trained about a pair of oppositely disposed pulleys 14 and 15 transports articles to be sprayed through the spraying chamber in a direction from right to left as viewed in Figure 1.

During passage through the enclosure 10, articles on the -conveyor belt 13 are sprayed with a liquid spray introduced from a conduit 17 through a nozzle or spray head 18. t

In order .to prevent the liquid spray while in suspension from being carried ,outside the enclosure 10,4 the spraying chamber is provided with curtain-type closures of the type shown. These enclosures include a pair of spaced pulleys 19 and 20 having reduced diameter shafts identied at 21 and 22. An endless driving belt 24 con.- nects the reducedl diameter shafts 21 and 22 of the two pulleys. A supporting belt 25 is trained `about the pulley 19, and a similar belt 26 is trained about the pulley 20. Each of the belts carriesa plurality of curtains in spaced relation therealong, the individual curtains being identied at numerals 27a `through 27h, Irespectively, on belt 25 and numerals 28a through 28h on belt 26. The width of the individual curtains is at least as great as the width of the conveyor belt 13. The length of each of the curtains is long enough so that the bottom of the curtain touches the surface of the conveyor belt 13 for a limited time as the supporting belts are driven. The spacing between adjacent curtains on both of the belts 25 `and 26 `is such that as one curtain leaves contact with the conveyor belt 13, the next succeeding curtain touches the surface ofthe conveyor belt 13. The spacing between the individual curtains will also depend somewhat upon the width of the article being transported on the conveyor belt so that one curtain touches the surface of the belt 13 immediately in front of the article being conveyed, while the next succeeding belt will touch the Surface of the conveyor belt 13` immediately behind the article. The lower ends of the individual curtains are also preferably weighted so that they hang down in a nearly vertical position with Vrespect to the surface of the conveyor belt 13.

The speed of rotation of the pulleys 19 and 20 is correlated with the speed of rotation of the pulleys 14 and 15, such that one of the curtains when engaging the conveyor belt has a linear velocity substantiallyequal to the linear velocity of the conveyor belt. For example, a mechanical linkage can be included between the pulleys 14 and 15 and the pulleys 19 and 20 to achieve this result, or alternatively, the speed of rotation of the pulleys 19 and 20 can be adjusted independently of the drive means rotating the pulleys 14 and 15 to accomplish the same result.

In the form of the invention illustrated in Figures 2 and 3, the supporting means for the individual curtains consist of a pair of chains 30 and 31 with supporting rods 32 extending between oppositely disposed links on the chains 30 and 31. In this form of the invention, the

curtain member kconsists of a piece of flexible strip material such as a piece of canvas 33 having one marginal edge portion 34 secured by stitching 3S to the opposite side of the canvas piece 33. The lower end of the canvas piece 33 is also bent into a loop and secured to the rear surface of the canvas piece 33 by means of stitching 36. A weighting rod 3S is snugly received within the loop formed in the bottom of the canvas piece 33 to act as a ballast for the curtain. The chains 30 and 31 of Figure 2 are arranged to be received on a pair of spaced sprockets (not shown), the sprockets and chains being used in lieu of the pulleys 19 and of the assembly shown in Figure l.

A still further modified form of the invention is illustrated in Figures 4 and 5. In this form of the invention, the supporting means for the curtains includes a drum 40 mounted on a shaft 41 and having peripherally spaced lugs 42 at one end thereof, and similar peripherally spaced lugs A43 at the opposite end thereof. The aligned lugs 42 and 43 receive a plurality of supporting bars 45. The structure of the curtain element itself can be identical with that illustrated in Figure 3, and includes a flexible web portion 46 of canvas or other suitable material provided with a weighting rod 47 at the lower end thereof.

Another form of the invention is illustrated in Figures 6 and 7 of the drawings. In this form of the invention, -a plurality of curtains 50 are carried by an endless belt 51 trained about a pair of spaced pulleys S2 and 53. The spacing between adjoining curtains 50 is greater than the length of an article A being conveyed on the conveyor belt 13, so that the movement of the curtains along the conveyor belt 13 does not interfere with the passage of the article. The curtains 50 are secured t`o the belt 51 in the manner illustrated in Figure 7, each of the curtains 50 having a marginal end portion secured by means of stitching 52 to the belt 51, and also having a loop at the bottom end thereof for snugly receiving a weighting rod 56.

The composition of the curtain elements in each of the embodiments illustrated in the drawings will depend upon the environment in which the curtain elements lare enclosed. For example, where the curtain elements are to serve as closures for furnaces or driers, heat resistant material such as asbestos and the like will be used. Where the closures are to be used to prevent water spray from a washing operation from leaving the spraying chamber, water and rust-resistant materials such as rubber, synthetic plastics and the like Will be employed.

From the foregoing it will be appreciated that the curtain-type closures of the present invention prevent particle loss, spray loss and heat loss from a treating chamber into which articles are being continuously passed. The curtain elements are simple in construction, and are readily replaceable.

It will be appreciated that various modifications and variations may be effected without departing from the scope of the novel concepts of the present invention.

I claim as my invention:

l. In an article treating apparatus including means delining an article treating chamber and conveying means for transporting articles to be treated through said chamber, a curtain-type closure comprising a plurality of individual curtains successively movable With respect to said conveying means to provide an end closure for said treating chamber each of said curtains being of flexible sheet material having a weighted free end gravity urged into cooperative relationship with said conveyor means.

2. In an article treating apparatus including means dening an article treating chamber and conveying means for transporting articles to be treated through said charnber, a curtain-type closure comprising rotary means, and a plurality of individual curtains carried by the periphery of said rotary means, said 'curtains being arranged to closely approach the surface of said conveying means successively to provide an end closure for said treating chamber.

3. In an articletreating apparatus including means dening an article treating chamber and conveying means for transporting articles through said chamber, a pair of spaced rotary means within said chamber, a plurality of closure elements secured along the periphery of said rotary means, and means interconnecting said pair of spaced rotary means to drive said rotary means at the same angular velocity.

4. In an article treating apparatus including means defining an article treating chamber and an endless belt for transporting articles through said chamber, a curtain-type closure comprising a rotary means, a plurality of individual curtains having end portions thereof secured to the periphery of said rotary means and being of sufficient length to engage the surface of said belt during rotation of said rotary means, and means for rotating said rotary means at a velocity such that one of said curtains when engaging said belt has a linear velocity substantially equal to the velocity of said belt.

5. In an article treating apparatus including means delining an article treating chamber and a moving endless belt for transporting articles through said chamber, a pair of spaced rotary means above said endless belt, a plurality of closure elements carried by the periphery of said rotary means, said closure elements being of suiicient length to successively engage the surface of said belt during rotation of said rotary means, and means interconnecting said rotary means and driving said rotary means at a velocity such that one of said closure elements when engaging said belt has a linear velocity substantially equal to the linear velocity of said belt.

6. A curtain-type closure for an article treating chamber which comprises a drum, spaced supporting means about the periphery of said drum, a plurality of rods secured by said supporting means about the periphery of said drum, and a depending curtain carried by each of said rods for continuous comovement with said drum While said chamber is in operation, each curtain comprising a flexible body portion and a Weighted end portion for retaining said curtains in an extended position during operation.

lReferences Cited inthe tile of this patent UNITED STATES PATENTS 624,111 vSnow May 2, 1899 641,947 Farrand Jan. 23, 1900 1,465,071 Baker Aug. 14, 1923 1,712,845 Riker et al. May 14, 1929 1,783,030 Worden Nov. 25, 1930 .2,164,056 Engelmann et al. June 27, 1939 2,295,732 Hess Sept. l5, 1942 

